727 research outputs found
An experimental investigation of collusion in hard-close auctions: partners and friends
We study collusion in the finitely repeated, hard-close auction experiment. Three subjects, identified by their bidder name, simultaneously compete in three auction markets. Due to the experimental design, subjects are enabled to the sharing of the benefits of cooperation by coordinating their individual demands. Similar collusive behavior has been suggested to play an important role in empirical markets (Klemperer 2002). We consider two treatments. In the first one, the partners treatment, subjects who are identified by bidder-names interact repeatedly but anonymously with each other. In the second one, the friends treatment, groups of three subjects who participate together in the experiment, interact repeatedly with another. In the experiment, we do not observe tacit collusion in the partners treatment; the outcome is efficient and prices converge quickly to the rational equilibrium prediction. Only in the friends treatment, cooperation gains can be realized, but much less cooperation is observed than one would imagine. We conclude that in the laboratory, cooperation is difficult to achieve in the hard-close auction market if anonymity prevails.multi unit auctions, collusion, experimental economics
A Theory of Jump Bidding in Ascending Auctions
Jump bidding is a commonly observed phenomenon that involves bidders in ascending auctions submitting bids higher than required by the auctioneer. Such behavior is typically explained as due to irrationality or to bidders signaling their value. We present field data that suggests such explanations are unsatisfactory and construct an alternative model in which jump bidding occurs due to strategic concerns and impatience. We go on to examine the impact of jump bidding on the outcome of ascending auctions in an attempt to resolve some policy disputes in the design of ascending auctions.auction theory, ascending auctions, jump bidding
Low Price Equilibrium in Multi-Unit Auctions: The GSM Spectrum Auction in Germany
The second-generation GSM spectrum auction in Germany is probably the most clear cut example of a low price outcome in a simultaneous ascending-bid auction.The present paper gives an account of the events, describes the auction rules and market conditions, and provides a theoretical explanation of low price equilibria in simultaneous, ascending-bid auctions.In particular it is shown that the low price equilibrium that implements the efficient allocation is the unique perfect equilibrium of that game.Multi-unit auctions, spectrum auctions, telecomm-unications, industrial organization, game theory
Heuristic bidding strategies for multiple heterogeneous auctions
This paper investigates utility maximising bidding heuristics for agents that participate in multiple heterogeneous auctions, in which the auction format and the starting and closing times can be different. Our strategy allows an agent to procure one or more items and to participate in any number of auctions. For this case, forming an optimal bidding strategy by global utility maximisation is computationally intractable, and so we develop two-stage heuristics that first provide reasonable bidding thresholds with simple strategies before deciding which auctions to participate in. The proposed approach leads to an average gain of at least 24% in agent utility over commonly used benchmarks
Auctions as Coordination Devices
This paper develops an economic argument relating auctions to high market prices. At the core of the argument is the claim that market competition and bidding in an auction should be analyzed as part of one game, where the pricing strategies in the market subgame depend on the bidding strategies during the auction. I show that when there are two licenses for sale the only equilibrium in the overall game that is consistent with the logic of forward induction is the one where firms bid an amount (almost) equal to the profits of the cooperative market outcome and follow a cooperative pricing strategy in the market game resulting in high prices. With three or more licenses the auction format determines whether the forward induction argument works.Auctions, Market prices, Coordination
On some collusive and signaling equilibria in ascending auctions for multiple objects
We consider two ascending auctions for multiple objects: the SEAMO (simultaneous English auction for multiple objects) and the the JAMO (Japanese auction for multiple objects). We first derive a (competitive) Perfect Bayesian Equilibrium of the JAMO by exploiting the strategic equivalence between the JAMO and the Survival Auction which consists of a finite sequence of sealed-bid auctions. Then, we prove that many of the (unwanted) collusive or signaling equilibria studied in the literature in the framework of the SEAMO do not have a counterpart in the JAMO. However, it is shown that certain collusive equilibria based on retaliatory strategies do exist in both auctions.Multi-unit auctions; Ascending auctions; FCC auctions; Collusion; Retaliation
Market Institutions: An Expository Essay
This essay provides an elementary, unified introduction to the models of market institutions that go beyond the competitive model of price-taking behavior on both sides of the market. Several models of market institutions that govern price determination are explored and compared, including contracting, posted prices, bilateral bargaining, middlemen, and auctions. While equilibrium models still do not capture the full possibilities for market behavior, modeling specific market institutions reduces the level of abstraction inherent in the standard competitive model.market institutions; contracting; posted prices; bilateral bargaining; middlemen; auctions
Optimal Real-Time Bidding Strategies
The ad-trading desks of media-buying agencies are increasingly relying on
complex algorithms for purchasing advertising inventory. In particular,
Real-Time Bidding (RTB) algorithms respond to many auctions -- usually Vickrey
auctions -- throughout the day for buying ad-inventory with the aim of
maximizing one or several key performance indicators (KPI). The optimization
problems faced by companies building bidding strategies are new and interesting
for the community of applied mathematicians. In this article, we introduce a
stochastic optimal control model that addresses the question of the optimal
bidding strategy in various realistic contexts: the maximization of the
inventory bought with a given amount of cash in the framework of audience
strategies, the maximization of the number of conversions/acquisitions with a
given amount of cash, etc. In our model, the sequence of auctions is modeled by
a Poisson process and the \textit{price to beat} for each auction is modeled by
a random variable following almost any probability distribution. We show that
the optimal bids are characterized by a Hamilton-Jacobi-Bellman equation, and
that almost-closed form solutions can be found by using a fluid limit.
Numerical examples are also carried out
Private Information in Sequential Common-Value Auctions
We study an infinitely-repeated ?rst-price auction with common values. Initially, bid- ders receive independent private signals about the objects' value, which itself does not change over time. Learning occurs only through observation of the bids. Under one-sided incomplete information, this information is eventually revealed and the seller extracts es- sentially the entire rent (for large discount factors). Both players?payo€s tend to zero as the discount factor tends to one. However, the uninformed bidder does relatively better than the informed bidder. We discuss the case of two-sided incomplete information, and argue that, under a Markovian re?nement, the outcome is pooling: information is revealed only insofar as it does not affect prices. Bidders submit a common, low bid in the tradition of collusion without conspiracy.repeated game with incomplete information; private information; ratchet effect; first-price auction; dynamic auctions
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